Patent Literature 1 discloses an electronic device in which an electronic component is provided to a depressed portion of a supporting body made of a liquid crystal polymer. Containing the electronic component in the depressed portion of the support is advantageous in that it makes it possible to prevent the electronic component from become a hindrance to mounting the support body to another support body (i.e., secondary mounting). Furthermore, liquid crystal polymer has excellent electrical properties, size stability, and heat resistance, and a layer of metal such as copper foil can be provided directly thereto via heating. This allows the liquid crystal polymer to be suitably used as a substrate for an electronic circuit.
A more detailed description of a component-mounted body obtained as a result of secondary mounting is as follows (such a body is hereinafter referred to as a “secondary component-mounted body”). FIG. 9 is a perspective view of an example of a secondary component-mounted body. Note that in FIG. 9, for convenience, a substrate for secondary mounting is depicted as a transparent member. As illustrated in FIG. 9, a substrate 111 for primary mounting has a depressed portion 114, in which an electronic component 120 is contained. Terminals of the electronic component 120 are connected via soldering 124, to first ends of wiring 112 provided to the substrate 111 for primary mounting. Second ends of the wiring 112 are connected, via soldering 150, to terminals (not shown) of a substrate 140 for secondary mounting.
Discussed next, with reference to FIG. 10, is a typical process of producing the secondary component-mounted body illustrated FIG. 9. FIG. 10 is a side view of an electronic component, a substrate for primary mounting, and a substrate for secondary mounting. There are two general types of production processes involving the steps illustrated in FIG. 10. The first type of production process is as follows. The substrate 111 for primary mounting begins in the state illustrated in (a) of FIG. 10, in which a depressed portion has not yet been formed. The electronic component 120 is placed on this substrate 111, and terminals of the electronic component 120 are electrically connected to the wiring 112 of the substrate 111 ((b) of FIG. 10). The substrate 111 is then bent so as to form the depressed portion 114 which contains the electronic component 120 ((d) of FIG. 10). Finally, the substrate 111 for primary mounting is electrically connected to the substrate 140 for secondary mounting ((e) of FIG. 10), and the secondary component-mounted body is completed. The second type of production process is as follows. The substrate 111 for primary mounting begins in the state illustrated in (a) of FIG. 10, in which a depressed portion has not yet been formed. Before the electronic component 120 is mounted to the substrate 111, the substrate 111 is bent so that the depressed portion 114 is formed ((c) of FIG. 10). Thereafter, the electronic component 120 is placed so as to be contained in the depressed portion 114, and terminals of the electronic component 120 are electrically connected to the wiring of the substrate 111 ((d) of FIG. 10). Finally, connection terminals of substrate 111 for primary mounting are electrically connected to connection terminals of the substrate 140 for secondary mounting ((e) of FIG. 10), and the secondary component-mounted body is completed.